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YNiC seminar 26th May
by Rebecca E Millman 22 May '11

22 May '11

Dear Users This Thursday (4-5 pm in YNiC) there will be a YNiC project proposal presentation given by Chris Racey. The title of the talk is "The effects of parametrically manipulating view exposure range on representational invariance in object selective cortex". Please see the abstract below. Everyone is welcome to attend. N.B. The starting time of the YNiC seminars will be 4 pm this term. Best wishes Rebecca *Abstract* Previously we have carried out two experiments in which view shift of objects and landscape scenes was parametrically manipulated. In both experiments participants viewed blocks of stimuli changing in view by 0, 5, 10, and 15°. Different levels of adaptation across these view shift conditions allow us to derive a measure of view sensitivity for any given voxel or region. We were able to show variation in the degree of view sensitivity between category selective regions for both objects and landscape stimuli. Our previous work has shed new light on how category specific visual information is processed and represented during perception. However, it is not yet clear what the effect of object learning and long term storage is on these ventral stream representations. Previous research on this issue is limited, and there have been few studies investigating the effects of prior learning on neural adaptation. We aim to apply our parametric manipulation of view shift paradigm during an encoding experiment with unfamiliar objects prior to scanning. Participants will under training, and learn to recognise objects where their range of view exposure will vary parametrically, from 0°, 10°, and 20°. In the scanner, all of the stimuli will be presented from previously unseen views in an fMR-adaptation block design, with blocks of images shifting in view in 10° steps. For each pre-exposure condition, the presentation conditions in the scanner will be identical, and any differences across conditions must be due to differences during the encoding of items. We predict that objects learned with a greater range of views will be associated with richer, more invariant, representations, and show greater degrees of invariant adaptation than objects learned under a narrower range of views. -- ************************************************************************ Dr. Rebecca E. Millman Science Liaison Officer York Neuroimaging Centre The Biocentre York Science Park Heslington YO10 5DG Tel: +44 (0) 1904 567614 Fax: +44 (0) 1904 435356

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YNiC Closed 27th May
by Jen Downing 19 May '11

19 May '11

Hi Everyone, Due to an important event taking place, please be aware that YNiC will be closed all day on Friday 27 May and there will be no scanning or access to the computers. The centre will be closed on Monday 30th due to the bank holiday and open again as usual on Tuesday 31st May. Best Wishes Jen

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Lies and statistics?
by Philip Quinlan 19 May '11

19 May '11

http://neuroskeptic.blogspot.com/2009/09/fmri-gets-slap-in-face-with-dead-f… ******************************************************************** Philip Quinlan E-Mail: ptq1(a)york.ac.uk Department of Psychology FAX: (01904) 323181 The University of York Tel: (01904) 320000 Ext. 3135 Heslington Direct : (01904) 323135 York YO10 5DD U.K. ********************************************************************

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smoking
by Gary Green 13 May '11

13 May '11

Dear Users Please do not smoke just outside the entrance to YNiC. Thank you Gary -- Gary Green York Neuroimaging Centre The Biocentre York Science Park Innovation Way Heslington York YO10 5DG http://www.ynic.york.ac.uk https://www.ynic.york.ac.uk/about-us/people/ggrg tel. +44 (0) 1904 435349 PA +44 (0) 1904 435329 or reception(a)ynic.york.ac.uk fax +44 (0) 1904 435356 mobile +44 (0) 788 191 3004

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[Fwd: Re: poststats inquiry pls]
by Gary Green 10 May '11

10 May '11

This email to the FSL mailserver list may be of interest to local YNiC FSL users Gary ---------------------------------- Dear David, The short answer is, no, there is no way to justify Z=1.7 as a cluster-forming threshold in FEAT. The problem is that the cluster size P-values are based on Random Field Theory (RFT), and RFT makes various approximation that are only valid for high thresholds. While one early reference (Petersson et al, 1999) specified cluster-forming threshold P=0.01 / Z=2.33 as a practical lower limit for accurate results, later work (Hayasaka & Nichols, 2003; Silver et al, 2010; K. Worsley personal communication) found even that level was unstable, and instead recommended P=0.001 / Z=3.09 as a lower limit on a cluster-forming threshold to ensure accurate inferences. On the other hand, if you are using randomise, you can safely use any cluster-forming threshold (though if you go too low, the clusters might be too extended and spindly to be interpretable). If using randomise, though, check out TFCE as away to avoid specifying any particular cluster-forming threshold. To answer your second question, the cluster-forming threshold used at lower-levels is only used to make inferences *at* the lower level, and is ignored at higher levels. Only the cluster-forming threshold specified in the top-level FEAT analysis matters for the top-level results. -Tom Petersson, K. M., Nichols, T. E., Poline, J.-B., & Holmes, A. P. (1999). Statistical limitations in functional neuroimaging II. Signal detection and statistical inference. /Phil. Trans. R. Soc. Lond. B/, /354/, 1261-1281. Hayasaka, S., & Nichols, T. (2003). Validating cluster size inference: random field and permutation methods. /NeuroImage/, /20/, 2343-2356. Silver, M., Montana, G., & Nichols, T. E. (2010). False positives in neuroimaging genetics using voxel-based morphometry data. /NeuroImage/. Elsevier Inc. doi: 10.1016/j.neuroimage.2010.08.049. On Mon, May 9, 2011 at 1:06 PM, David Soto <d.soto.b(a)gmail.com <mailto:d.soto.b@gmail.com>> wrote: Hello, I am finding that when I use a Z<1.7 to define the cluster size at he highest level analyses, I am getting some interesting activations in regions that I don't see when I use Z<2.3. In both cases I use cluster thresholding and p<0.05 whole brain corrected..... I know the Z value used to define cluster size prior to correction for multiple comparisons is arbitrary, but is it there any paper that I can use to justify in my study why a Z<1.7 was used instead of Z<2.3? Would it be right to say that poststat results with a Z<1.7 are more lenient than with a Z<2.3? I feel it this is not necessarily right but can you please advise? A second question I have is about poststats as implemented in FEAT.... Say that I have done a lower level analyses - for session, a 2nd level -across session within subjects- and 3rd level -across subjects- do I need to set up the Z<1.7 at the first and second level and third level analyses - or does FEAT bring the unthresholded data from lower level analyses to the higher levels and then use the Z score specified at the highest level analyses? in other words, will I get the same results if I specify Z<1.7 across all levels or whether I do Z<2.3 for first and second level and Z<1.7 at the higher level? Many thanks, David -- ____________________________________________ Thomas Nichols, PhD Principal Research Fellow, Head of Neuroimaging Statistics Department of Statistics & Warwick Manufacturing Group University of Warwick Coventry CV4 7AL United Kingdom Email: t.e.nichols(a)warwick.ac.uk <mailto:t.e.nichols@warwick.ac.uk> Phone, Stats: +44 24761 51086, WMG: +44 24761 50752 Fax: +44 24 7652 4532

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External Seminar Today
by Julian Oldmeadow 10 May '11

10 May '11

Dear All, Today's external seminar will be delivered by Prof. Michelle Ryan from Exeter. Her talk will follow on nicely from last wednesday's Athena Swan talk, as she will be presenting her research on the "Glass Cliff", a precarious and obscured obstacle faced by women in leadership. As usual there will be drinks in the foyer afterwards. 4:15 in B020. Please come. Julian Julian Oldmeadow, PhD Department of Psychology University of York York, YO10 5DD julian.oldmeadow(a)york.ac.uk

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[Fwd: Neuroimaging post]
by Gary Green 10 May '11

10 May '11

FYI ---------------------------------- Applications are invited for a position at a Hospital Research Center in Barcelona, Spain. The position is full-time for 15 months (with a probable extension to 18 months). It entails working mainly on neuroimaging data. The postholder will help in analyzing functional, structural, and diffusion tensor data. Essential skills include knowledge of fMRI and/or structural MRI techniques, a proficient management of SPM and programming skills in MATLAB. The position is available to start 1st of September 2011. Annual salary will be around €26,000 (plus social security, health and unemployment benefits). Please send enquiries or applications (which must include a covering letter detailing professional objectives and interests, CV, all in one pdf file) to cenicogni(a)gmail.com, with the subject line "Neuroimaging position". -- Gary

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[Fwd: Postdoctoral fellowships at Oxford University on brain basis of visual attention and associative processing and disruption and retraining of these mechanisms in anxiety]
by Gary Green 10 May '11

10 May '11

FYI ----------------------- Positions to be based at The Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Oxford University. From June 2011 part of my lab (primarily at UC Berkeley) will be based at The Centre for Functional Magnetic Resonance Imaging of the Brain (FMRIB), Oxford University. I am looking for two postdoctoral researchers to join the group there. The positions are to play a key role in a programme of research aimed at identifying and retraining the brain mechanisms underlying disrupted attentional and associative processing in anxiety. The research is supported by funding from the European Research Council and conducted in collaboration with Drs K Weich, I Tracey and E Holmes. Candidates are sought with a doctorate in a relevant discipline and research experience in neuroimaging and programming (ideally in matlab or python). Employment is for an initial period of 1 year with the possibility of extension for an addition 2-4 years. Salary is from £33084. Start date is flexible between July 1 and Dec 1 2011. Further details can be obtained from sbishop(a)berkeley.edu <mailto:sbishop@berkeley.edu>. Prof. Sonia Bishop Assistant Professor Dept Psychology & Helen Wills Neuroscience Institute, UC Berkeley; visiting Senior Researcher, FMRIB, Oxford University

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[Fwd: PostDoc- and PhD-positions at the Central Institute of Mental Health in Germany (ZI Mannheim)]
by Gary Green 10 May '11

10 May '11

FYI -------------------------------------------------------------------------------------------------------------- The Central Institute of Mental Health in Mannheim, Germany, is an internationally renowned research institute in the field of psychiatry and neuroscience, home of the Department of Psychiatry and Psychotherapy of the Medical Faculty Mannheim of the University of Heidelberg, and a psychiatric hospital with 255 inpatient and 52 day-clinic beds. To strengthen our recently established independent neuroscience research group funded by the Federal Ministry of Education and Research (BMBF), the Clinic for Psychiatry and Psychotherapy (Medical Director: Prof. Dr. med. Andreas Meyer-Lindenberg) offers * * *1 PostDoc and 1 PhD-Student Position* * * in the area of functional and structural magnetic resonance imaging (MRI). Positions are initially limited to 2 years, a prolongation is intended. The Central Institute of Mental Health is equipped, among others, with two Siemens 3 Tesla research MR scanners. Our research group consists of an interdisciplinary team of psychologists, psychiatrists, neurologists, biologists and technical assistants (http://www.zi-mannheim.de/ag_imaging.html). The main goal of the international research project is to examine fronto-striatal plasticity processes and their molecular genetic basis in healthy individuals and psychiatric patients using multimodal magnetic resonance imaging techniques (fMRI, morphometry, DTI, spectroscopy). Ideally, potential applicants will have previous experience with the acquisition, processing and analysis of MRI data, as well as a strong interest in the application of systems neuroscience methods in the context of neuropsychiatric research questions. We offer an interesting job in a pleasant working environment at a leading German research institute. Salary is according to the German TV-L pay scale, including the social benefits of the German public service sector. For further information please contact Dr. Dr. Heike Tost, Tel. +49 621 1703-6508, E-Mail heike.tost(a)zi-mannheim.de <mailto:heike.tost@zi-mannheim.de>. ____________________________________ Maria Zangl, PhD-Student Central Institute of Mental Health Research Group Imaging in Psychiatry J5, 68159 Mannheim, Germany Phone: +49-621-1703-6514 Email:maria.zangl@zi-mannheim.de <mailto:maria.zangl@zi-mannheim.de>

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Niedermeyer's Electroencephalography
by michael＠ynic.york.ac.uk 19 Apr '11

19 Apr '11

Dear all, does anyone have a recent edition of Niedermeyer's Electroencephalography: Basic Principles, Clinical Applications and Related Fields? If so, would I be able to borrow it? Thanks, Michael

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